Quick Frame Stiffiner Question

[USAF_XJ]

I'm new to the board here and after quite a bit of searching I haven't quite found the answer I am looking for. I am in the process of building my 1998 XJ and ready to do frame stiffiners. The engine is currently out getting machined for a 4.6 stroker build. My question is, is it ok to install frame stiffiners with the engine out? My expecience with unibody vehicles has only been mustangs and when installing chassis stiffining and frame connectors on those cars I always needed the weight of the drivtrain in them for them to be straight. Is that an issue with an XJ?

 

[RCP Phx]

If anything it gives you more room to make it all right!

 

[ChuckQue]

I'm new to the board here and after quite a bit of searching I haven't quite found the answer I am looking for. I am in the process of building my 1998 XJ and ready to do frame stiffiners. The engine is currently out getting machined for a 4.6 stroker build. My question is, is it ok to install frame stiffiners with the engine out? My expecience with unibody vehicles has only been mustangs and when installing chassis stiffining and frame connectors on those cars I always needed the weight of the drivtrain in them for them to be straight. Is that an issue with an XJ?

This is actually a really good question and a valid point…..hopefully someone chimes in with an answer.

 

[XJlimitedx99]

My gut feeling is that it will be fine to weld them with the drivetrain out of it. The drivetrain and suspension are all soft-mounted anyway.

Just my opinion. This is a good question. Not sure I've ever seen it asked before.

 

[SlowXj]

You'll be just fine. The xj gets a bad name for being weak (and it is) but compared to a car it's pretty stout... we say weak in comparison to full frame trucks.

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[75SV1]

I plan to have a set welded in with out the trans and motor in there. I did have a set welded in last year with the engine and everything in place. It was requested to remove the interior for this next one. Have axles and steering in place for moving. It would cost less.

Edit: on another vehicle, I purchased a tower brace or shock brace. The instruction as I remember is to jack up the vehicle to get the weight off the tires so the towers don't lean in.

 

[Evan03]

It's a jeep it left the factory crooked

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[USAF_XJ]

Seems like the general consensus so far is it won't be an issue. It makes sense seeing as the other cars I've mentioned needed subframe connectors while at least the Jeep is already connected and shouldn't flex too much just with the engine out. I think I'll go ahead and weld these in even if the engine doesn't get back in.

 

[75SV1]

Just a thought. The FSM should have dimensions for what the frame should be. So, possibly shim the frame to those, then weld in the stiffeners.

 

[SlowXj]

It's a jeep it left the factory crooked

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Bahahaha! YES! This is the comment to live by lmao

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[USAF_XJ]

One last question regarding frame stiffiners. I purchased the Ruff Stuff stiffiners and I was wondering what interference they would cause with aftermarket bumpers? Specifically the Smittybilt front winch bumper?

 

[Evan03]

I'd have to do some research picture surfing on both those products to answer that. So ill just bump the thread

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[75SV1]

One last question regarding frame stiffiners. I purchased the Ruff Stuff stiffiners and I was wondering what interference they would cause with aftermarket bumpers? Specifically the Smittybilt front winch bumper?

I do have frame stiffeners and went with a Bad Dad Fab hidden winch bumper set up. He had to space out for the frame stiffeners. I don't know if there are frame stiffeners that have the extension for the bumper mount.
Also, which Ruff Stuff frame stiffener did you go with? I went with the $8- to $90 ones for the front. It didn't have holes for some of the frame holes. Their $165 ones look better.

 

[USAF_XJ]

I do have frame stiffeners and went with a Bad Dad Fab hidden winch bumper set up. He had to space out for the frame stiffeners. I don't know if there are frame stiffeners that have the extension for the bumper mount.
Also, which Ruff Stuff frame stiffener did you go with? I went with the $8- to $90 ones for the front. It didn't have holes for some of the frame holes. Their $165 ones look better.

I went with their $165 ones that should keep most of the factory holes as they are.

 

[89Mock]

I'd have to do some research picture surfing on both those products to answer that. So ill just bump the thread

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The front portion of the Ruffstuff front unibody stiffeners will compete with the smittybuilt bumper for space. The smittybuilt bumper I have comes back on the driver side and works as a brace for the steering box. They are 3/16” thick so you’re adding 3/8” width under the bumper designed to Mount in factory locations.

 

[89Mock]

Picture above is with smittybuilt bumper and Ruffstuff fromt stiffener installed except for the front piece. In case someone didn’t know.

 

[USAF_XJ]

Picture above is with smittybuilt bumper and Ruffstuff fromt stiffener installed except for the front piece. In case someone didn’t know.

Thanks for that awesome picture, that is exactly what I needed to see. So I would have to just not weld up the front portion which looks like what you did. Or I might have to go the DIY bumper kit route so that its easier for me to make that modification since I really like the idea of using the plates as a steering box stiffiner too.

 

[75SV1]

Thanks for that awesome picture, that is exactly what I needed to see. So I would have to just not weld up the front portion which looks like what you did. Or I might have to go the DIY bumper kit route so that its easier for me to make that modification since I really like the idea of using the plates as a steering box stiffiner too.

Note that the rear access hole for the upper control arm would need to be opened up. Look like in the picture the front of the stiffener plate is cut off to accommodate the bumper plate. I'd probably cut the front plate to match the profile of the bumper plate and weld the bumper plate in place too. Basically, the frame stiffener plate is just missing the front bolt hole for the bumper.

 

[89Mock]

Correct. The rear piece of the front frame stiffeners (paddle shaped piece) completely covers the upper control arm bolt hole.

Driver side without paddle shaped piece welded on

Passenger side with paddle shaped piece welded on.

Another photo of the middle portion looking towards the bumper.

This is going to get weird when I want to remove the upper control arm. I’ll have to cut the bolt and see what kind of luck I have with the bolt head falling out somewhere in the unibody. This is what happens when you don’t plan ahead. Maybe I’ll just leave it in place with a nut holding the bolt in place.

 

[USAF_XJ]

Correct. The rear piece of the front frame stiffeners (paddle shaped piece) completely covers the upper control arm bolt hole.

Driver side without paddle shaped piece welded on

Passenger side with paddle shaped piece welded on.

Another photo of the middle portion looking towards the bumper.

This is going to get weird when I want to remove the upper control arm. I’ll have to cut the bolt and see what kind of luck I have with the bolt head falling out somewhere in the unibody. This is what happens when you don’t plan ahead. Maybe I’ll just leave it in place with a nut holding the bolt in place.

Oh yeah I would have not thought about that at all. I do plan on installing Iron Rock Off-Raod's 3 link long arm at the same time so it wont be an issue but I would not have thought to take those out before I weld.